Question

13. A building is subjected to an explosion at the ground level of 200 lbs. at a standoff distance of 150 ft. a) What is the reflected pressure and reflected impulse of the explosion? (4 pts) b) If a wall facing the blast has a natural time period of 80 milliseconds, what is the nature of blast that experiences? (Impulsive, dynamic or quasistatic). Show details of your answer? (6 pts)

Answer 1

Reflected pressure = Pr = 2Pso{(7P0+4Pso)/(7Po+Pso)} W= 200lbs =90.71kg

R= 150 ft =45.72

scaled distance Z = R/W^1/3 = 45.72/90.71^1/3= 10.175 m

Pso = (0.975/z + 1.455/z2 + 5.85 / z3) -0.019 = 0.1 bar

Po = 1bar

Reflected pressure = 0.2 * 1,042=0.0416 bar

Reflected impulse

maximum peak pressure Pr and time duration td, which yields the reflected impulse ir

ir = 1/2 (Pr *td) = 0.5 * 0.0416 * 0.08 = 0.00166